A through-hole as a mouthpiece is provided on the body of a mobile phone that is a typical information and telecommunications equipment. In order to prevent foreign objects such as dust, water drops and the like from entering this through-hole and thus causing malfunctions, a film called a sound-permeable film is disposed inside the body (JP 2003-53872 A).
A sound-permeable film is generally composed of a nonwoven fabric or a resin porous membrane, which prevents foreign objects such as water drops and the like from entering the body, while ensuring the excellent sound permeability between the inside and outside of the body.